1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2017-2018 HUAWEI, Inc. 4 * https://www.huawei.com/ 5 * Copyright (C) 2021, Alibaba Cloud 6 */ 7 #include "xattr.h" 8 9 #include <trace/events/erofs.h> 10 11 static void *erofs_read_inode(struct erofs_buf *buf, 12 struct inode *inode, unsigned int *ofs) 13 { 14 struct super_block *sb = inode->i_sb; 15 struct erofs_sb_info *sbi = EROFS_SB(sb); 16 struct erofs_inode *vi = EROFS_I(inode); 17 const erofs_off_t inode_loc = erofs_iloc(inode); 18 erofs_blk_t blkaddr, nblks = 0; 19 void *kaddr; 20 struct erofs_inode_compact *dic; 21 struct erofs_inode_extended *die, *copied = NULL; 22 union erofs_inode_i_u iu; 23 unsigned int ifmt; 24 int err; 25 26 blkaddr = erofs_blknr(sb, inode_loc); 27 *ofs = erofs_blkoff(sb, inode_loc); 28 29 kaddr = erofs_read_metabuf(buf, sb, blkaddr, EROFS_KMAP); 30 if (IS_ERR(kaddr)) { 31 erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld", 32 vi->nid, PTR_ERR(kaddr)); 33 return kaddr; 34 } 35 36 dic = kaddr + *ofs; 37 ifmt = le16_to_cpu(dic->i_format); 38 if (ifmt & ~EROFS_I_ALL) { 39 erofs_err(sb, "unsupported i_format %u of nid %llu", 40 ifmt, vi->nid); 41 err = -EOPNOTSUPP; 42 goto err_out; 43 } 44 45 vi->datalayout = erofs_inode_datalayout(ifmt); 46 if (vi->datalayout >= EROFS_INODE_DATALAYOUT_MAX) { 47 erofs_err(sb, "unsupported datalayout %u of nid %llu", 48 vi->datalayout, vi->nid); 49 err = -EOPNOTSUPP; 50 goto err_out; 51 } 52 53 switch (erofs_inode_version(ifmt)) { 54 case EROFS_INODE_LAYOUT_EXTENDED: 55 vi->inode_isize = sizeof(struct erofs_inode_extended); 56 /* check if the extended inode acrosses block boundary */ 57 if (*ofs + vi->inode_isize <= sb->s_blocksize) { 58 *ofs += vi->inode_isize; 59 die = (struct erofs_inode_extended *)dic; 60 } else { 61 const unsigned int gotten = sb->s_blocksize - *ofs; 62 63 copied = kmalloc(vi->inode_isize, GFP_KERNEL); 64 if (!copied) { 65 err = -ENOMEM; 66 goto err_out; 67 } 68 memcpy(copied, dic, gotten); 69 kaddr = erofs_read_metabuf(buf, sb, blkaddr + 1, 70 EROFS_KMAP); 71 if (IS_ERR(kaddr)) { 72 erofs_err(sb, "failed to get inode payload block (nid: %llu), err %ld", 73 vi->nid, PTR_ERR(kaddr)); 74 kfree(copied); 75 return kaddr; 76 } 77 *ofs = vi->inode_isize - gotten; 78 memcpy((u8 *)copied + gotten, kaddr, *ofs); 79 die = copied; 80 } 81 vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount); 82 83 inode->i_mode = le16_to_cpu(die->i_mode); 84 iu = die->i_u; 85 i_uid_write(inode, le32_to_cpu(die->i_uid)); 86 i_gid_write(inode, le32_to_cpu(die->i_gid)); 87 set_nlink(inode, le32_to_cpu(die->i_nlink)); 88 /* each extended inode has its own timestamp */ 89 inode_set_ctime(inode, le64_to_cpu(die->i_mtime), 90 le32_to_cpu(die->i_mtime_nsec)); 91 92 inode->i_size = le64_to_cpu(die->i_size); 93 kfree(copied); 94 copied = NULL; 95 break; 96 case EROFS_INODE_LAYOUT_COMPACT: 97 vi->inode_isize = sizeof(struct erofs_inode_compact); 98 *ofs += vi->inode_isize; 99 vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount); 100 101 inode->i_mode = le16_to_cpu(dic->i_mode); 102 iu = dic->i_u; 103 i_uid_write(inode, le16_to_cpu(dic->i_uid)); 104 i_gid_write(inode, le16_to_cpu(dic->i_gid)); 105 set_nlink(inode, le16_to_cpu(dic->i_nlink)); 106 /* use build time for compact inodes */ 107 inode_set_ctime(inode, sbi->build_time, sbi->build_time_nsec); 108 109 inode->i_size = le32_to_cpu(dic->i_size); 110 break; 111 default: 112 erofs_err(sb, "unsupported on-disk inode version %u of nid %llu", 113 erofs_inode_version(ifmt), vi->nid); 114 err = -EOPNOTSUPP; 115 goto err_out; 116 } 117 118 switch (inode->i_mode & S_IFMT) { 119 case S_IFREG: 120 case S_IFDIR: 121 case S_IFLNK: 122 vi->raw_blkaddr = le32_to_cpu(iu.raw_blkaddr); 123 break; 124 case S_IFCHR: 125 case S_IFBLK: 126 inode->i_rdev = new_decode_dev(le32_to_cpu(iu.rdev)); 127 break; 128 case S_IFIFO: 129 case S_IFSOCK: 130 inode->i_rdev = 0; 131 break; 132 default: 133 erofs_err(sb, "bogus i_mode (%o) @ nid %llu", inode->i_mode, 134 vi->nid); 135 err = -EFSCORRUPTED; 136 goto err_out; 137 } 138 139 /* total blocks for compressed files */ 140 if (erofs_inode_is_data_compressed(vi->datalayout)) { 141 nblks = le32_to_cpu(iu.compressed_blocks); 142 } else if (vi->datalayout == EROFS_INODE_CHUNK_BASED) { 143 /* fill chunked inode summary info */ 144 vi->chunkformat = le16_to_cpu(iu.c.format); 145 if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) { 146 erofs_err(sb, "unsupported chunk format %x of nid %llu", 147 vi->chunkformat, vi->nid); 148 err = -EOPNOTSUPP; 149 goto err_out; 150 } 151 vi->chunkbits = sb->s_blocksize_bits + 152 (vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK); 153 } 154 inode_set_mtime_to_ts(inode, 155 inode_set_atime_to_ts(inode, inode_get_ctime(inode))); 156 157 inode->i_flags &= ~S_DAX; 158 if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) && 159 (vi->datalayout == EROFS_INODE_FLAT_PLAIN || 160 vi->datalayout == EROFS_INODE_CHUNK_BASED)) 161 inode->i_flags |= S_DAX; 162 163 if (!nblks) 164 /* measure inode.i_blocks as generic filesystems */ 165 inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9; 166 else 167 inode->i_blocks = nblks << (sb->s_blocksize_bits - 9); 168 return kaddr; 169 170 err_out: 171 DBG_BUGON(1); 172 kfree(copied); 173 erofs_put_metabuf(buf); 174 return ERR_PTR(err); 175 } 176 177 static int erofs_fill_symlink(struct inode *inode, void *kaddr, 178 unsigned int m_pofs) 179 { 180 struct erofs_inode *vi = EROFS_I(inode); 181 unsigned int bsz = i_blocksize(inode); 182 char *lnk; 183 184 /* if it cannot be handled with fast symlink scheme */ 185 if (vi->datalayout != EROFS_INODE_FLAT_INLINE || 186 inode->i_size >= bsz || inode->i_size < 0) { 187 inode->i_op = &erofs_symlink_iops; 188 return 0; 189 } 190 191 lnk = kmalloc(inode->i_size + 1, GFP_KERNEL); 192 if (!lnk) 193 return -ENOMEM; 194 195 m_pofs += vi->xattr_isize; 196 /* inline symlink data shouldn't cross block boundary */ 197 if (m_pofs + inode->i_size > bsz) { 198 kfree(lnk); 199 erofs_err(inode->i_sb, 200 "inline data cross block boundary @ nid %llu", 201 vi->nid); 202 DBG_BUGON(1); 203 return -EFSCORRUPTED; 204 } 205 memcpy(lnk, kaddr + m_pofs, inode->i_size); 206 lnk[inode->i_size] = '\0'; 207 208 inode->i_link = lnk; 209 inode->i_op = &erofs_fast_symlink_iops; 210 return 0; 211 } 212 213 static int erofs_fill_inode(struct inode *inode) 214 { 215 struct erofs_inode *vi = EROFS_I(inode); 216 struct erofs_buf buf = __EROFS_BUF_INITIALIZER; 217 void *kaddr; 218 unsigned int ofs; 219 int err = 0; 220 221 trace_erofs_fill_inode(inode); 222 223 /* read inode base data from disk */ 224 kaddr = erofs_read_inode(&buf, inode, &ofs); 225 if (IS_ERR(kaddr)) 226 return PTR_ERR(kaddr); 227 228 /* setup the new inode */ 229 switch (inode->i_mode & S_IFMT) { 230 case S_IFREG: 231 inode->i_op = &erofs_generic_iops; 232 if (erofs_inode_is_data_compressed(vi->datalayout)) 233 inode->i_fop = &generic_ro_fops; 234 else 235 inode->i_fop = &erofs_file_fops; 236 break; 237 case S_IFDIR: 238 inode->i_op = &erofs_dir_iops; 239 inode->i_fop = &erofs_dir_fops; 240 inode_nohighmem(inode); 241 break; 242 case S_IFLNK: 243 err = erofs_fill_symlink(inode, kaddr, ofs); 244 if (err) 245 goto out_unlock; 246 inode_nohighmem(inode); 247 break; 248 case S_IFCHR: 249 case S_IFBLK: 250 case S_IFIFO: 251 case S_IFSOCK: 252 inode->i_op = &erofs_generic_iops; 253 init_special_inode(inode, inode->i_mode, inode->i_rdev); 254 goto out_unlock; 255 default: 256 err = -EFSCORRUPTED; 257 goto out_unlock; 258 } 259 260 if (erofs_inode_is_data_compressed(vi->datalayout)) { 261 #ifdef CONFIG_EROFS_FS_ZIP 262 DO_ONCE_LITE_IF(inode->i_blkbits != PAGE_SHIFT, 263 erofs_info, inode->i_sb, 264 "EXPERIMENTAL EROFS subpage compressed block support in use. Use at your own risk!"); 265 inode->i_mapping->a_ops = &z_erofs_aops; 266 err = 0; 267 goto out_unlock; 268 #endif 269 err = -EOPNOTSUPP; 270 goto out_unlock; 271 } 272 inode->i_mapping->a_ops = &erofs_raw_access_aops; 273 mapping_set_large_folios(inode->i_mapping); 274 #ifdef CONFIG_EROFS_FS_ONDEMAND 275 if (erofs_is_fscache_mode(inode->i_sb)) 276 inode->i_mapping->a_ops = &erofs_fscache_access_aops; 277 #endif 278 279 out_unlock: 280 erofs_put_metabuf(&buf); 281 return err; 282 } 283 284 /* 285 * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down 286 * so that it will fit. 287 */ 288 static ino_t erofs_squash_ino(erofs_nid_t nid) 289 { 290 ino_t ino = (ino_t)nid; 291 292 if (sizeof(ino_t) < sizeof(erofs_nid_t)) 293 ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8; 294 return ino; 295 } 296 297 static int erofs_iget5_eq(struct inode *inode, void *opaque) 298 { 299 return EROFS_I(inode)->nid == *(erofs_nid_t *)opaque; 300 } 301 302 static int erofs_iget5_set(struct inode *inode, void *opaque) 303 { 304 const erofs_nid_t nid = *(erofs_nid_t *)opaque; 305 306 inode->i_ino = erofs_squash_ino(nid); 307 EROFS_I(inode)->nid = nid; 308 return 0; 309 } 310 311 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid) 312 { 313 struct inode *inode; 314 315 inode = iget5_locked(sb, erofs_squash_ino(nid), erofs_iget5_eq, 316 erofs_iget5_set, &nid); 317 if (!inode) 318 return ERR_PTR(-ENOMEM); 319 320 if (inode->i_state & I_NEW) { 321 int err = erofs_fill_inode(inode); 322 323 if (err) { 324 iget_failed(inode); 325 return ERR_PTR(err); 326 } 327 unlock_new_inode(inode); 328 } 329 return inode; 330 } 331 332 int erofs_getattr(struct mnt_idmap *idmap, const struct path *path, 333 struct kstat *stat, u32 request_mask, 334 unsigned int query_flags) 335 { 336 struct inode *const inode = d_inode(path->dentry); 337 338 if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout)) 339 stat->attributes |= STATX_ATTR_COMPRESSED; 340 341 stat->attributes |= STATX_ATTR_IMMUTABLE; 342 stat->attributes_mask |= (STATX_ATTR_COMPRESSED | 343 STATX_ATTR_IMMUTABLE); 344 345 generic_fillattr(idmap, request_mask, inode, stat); 346 return 0; 347 } 348 349 const struct inode_operations erofs_generic_iops = { 350 .getattr = erofs_getattr, 351 .listxattr = erofs_listxattr, 352 .get_inode_acl = erofs_get_acl, 353 .fiemap = erofs_fiemap, 354 }; 355 356 const struct inode_operations erofs_symlink_iops = { 357 .get_link = page_get_link, 358 .getattr = erofs_getattr, 359 .listxattr = erofs_listxattr, 360 .get_inode_acl = erofs_get_acl, 361 }; 362 363 const struct inode_operations erofs_fast_symlink_iops = { 364 .get_link = simple_get_link, 365 .getattr = erofs_getattr, 366 .listxattr = erofs_listxattr, 367 .get_inode_acl = erofs_get_acl, 368 }; 369